(19)
(11) EP 1 915 850 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
13.07.2016 Bulletin 2016/28

(21) Application number: 06813571.4

(22) Date of filing: 18.08.2006
(51) International Patent Classification (IPC): 
H04M 7/00(2006.01)
(86) International application number:
PCT/US2006/032484
(87) International publication number:
WO 2007/022461 (22.02.2007 Gazette 2007/08)

(54)

METHODS, SYSTEMS, AND COMPUTER PROGRAM PRODUCTS FOR SUPPORTING TRANSCODER-FREE OPERATION IN MEDIA GATEWAY

VERFAHREN, SYSTEME UND COMPUTERPROGRAMMPRODUKTE ZUR UNTERSTÜTZUNG VON TRANSCODERFREIEM BETRIEB IN EINEM MEDIEN-GATEWAY

PROCEDES, SYSTEMES ET PROGRAMMES INFORMATIQUES PERMETTANT DE PRENDRE EN CHARGE UNE OPERATION SANS TRANSCODEUR DANS UNE PASSERELLE MULTIMEDIA


(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR

(30) Priority: 19.08.2005 US 207572

(43) Date of publication of application:
30.04.2008 Bulletin 2008/18

(73) Proprietor: Genband US LLC
Wilmington, DE 19808 (US)

(72) Inventors:
  • CHEN, Weisheng
    Allen, TX 75013 (US)
  • CHANG, Eric, C.
    Plano, TX 75075 (US)

(74) Representative: Isarpatent 
Patent- und Rechtsanwälte Behnisch Barth Charles Hassa Peckmann & Partner mbB Postfach 44 01 51
80750 München
80750 München (DE)


(56) References cited: : 
EP-A1- 1 465 445
US-A1- 2004 252 681
US-A1- 2005 076 108
US-B1- 6 671 367
US-A1- 2004 100 914
US-A1- 2005 074 017
US-A1- 2005 124 299
US-B1- 6 898 208
   
  • EDITORS TS 23 153: "Draft TS 23.153 Version 2.1.0", 3GPP DRAFT; N4-000892, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. CN WG4, no. Stockholm, Sweden; 20001110, 5 January 2001 (2001-01-05), XP050407571, [retrieved on 2001-01-05]
   
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

TECHNICAL FIELD



[0001] The subject matter described herein relates to implementing transcoder-free operation in a telecommunications network. More particularly, the subject matter described herein relates to methods, systems, and computer program products for implementing transcoder-free operation in a media gateway.

BACKGROUND ART



[0002] In telecommunications networks, codecs are devices that encode and decode voice signals transmitted over the network. Conventionally, uniform pulse code modulation (PCM) was used to encode voice sent over the telecommunications network. Uniform PCM involves sampling voice signals at a rate of 8,000 samples per second and 8 bits per sample, resulting in a 64 kbps codec rate. More recently, in mobile communications networks, adaptive modulation rate (AMR) codecs have been developed in which encoding and decoding rates change during a call. AMR is used to reduce the bandwidth used by voice calls.

[0003] One problem associated with using AMR codecs or other different types of codecs is that transcoding may be required when the source and destination devices use incompatible codecs. Transcoding is a process by which a voice signal encoded according to one rate and encoding standard is converted to another rate and another encoding standard. One problem with performing transcoding is that it can introduce latency and degradation in the voice signal being transmitted.

[0004] Figure 1 is a block diagram illustrating transcoders performing transcoding of a speech signal in a telecommunications network. Referring to Figure 1, a first transcoder 100 receives an AMR voice signal at an IuUP or NbUP interface of a 3GPP UMTS network. Transcoder 100 performs atranscoding operation by which the AMR voice signal is converted to PCM and forwards the signal to transcoder 102. Transcoder 100 introduces latency and voice degradation into the signal. The latency and voice degradation introduced by transcoder 100 is indicated by T1 in Figure 1.

[0005] Transcoder 102 receives the PCM signal from transcoder 100 and performs a second transcoding operation, converting the PCM signal to AMR rate 1, the same AMR rate received by the first transcoder. Transcoder 102 introduces further latency and voice quality degradation into the signal. The latency and voice quality degradation introduced by transcoder 102 is indicated by T2 in Figure 1. In the example illustrated in Figure 1, because the ingress and egress AMR rates are equal, transcoding is unnecessary. However, transcoding is performed because no intelligence exists in the network illustrated in this example to eliminate transcoding.

[0006] In order to avoid the difficulties associated with transcoding, methods for transcoder-free operation have been developed. Transcoder-free operation refers to operation in which a connection that is established between telecommunications endpoints, such as mobile telephones, that have compatible codecs where the connection does not use transcoders. Figure 2 is a block diagram of a conventional transcoder-free operation implementation developed by the assignee of the present application for use in a media gateway, referred to as the SanteraOne™ media gateway. Referring to Figure 2, media gateway 200 includes a plurality of packet network interfaces 202 for interfacing core networks, such as radio network control (RNC)/core network 205, that interface with voice over IP devices, such as mobile phones 204, an ATM switching fabric 206, voice servers 208, a TDM matrix 210, and TDM network interfaces 212. ATM switching fabric 206 establishes connections between packet network interfaces 202 and voice servers 208. Voice servers 208 perform voice processing functions, such as transcoding, encoding, and decoding. In the illustrated example, each voice server 208 includes a DSP 214 that implements a codec function. TDM matrix 210 switches TDM channels between TDM network interfaces 212 and voice servers 208. TDM matrix 210 also includes an HDLC bus 216 that interconnects DSPs on different voice servers. TDM network interfaces 212 interface with TDM based telecommunications endpoints.

[0007] In the example illustrated in Figure 2, in order to implement a transcoder-free connection, two codecs and two HDLC channels are used. That is, one DSP 214 on voice server 108 monitors the rate of an encoder used by a first telecommunications endpoint and the other DSP 214 on a separate voice server card monitors the encoding rate being used by the other endpoint. Rates and rate changes are communicated between the codecs using the HDLC connections. No transcoding is performed by either voice server because the ingress and egress codec rates are the same.

[0008] One problem associated with the transcoder-free operation of the media gateway 200 illustrated in Figure 2 it requires separate DPSs to monitor each endpoint of the connection Another problem is that the DSPs must be interconnected using two HDLC connections. Establishing each HDLC connection requires complex connection establishment procedures.

[0009] Document US 2005/0124299 A1 discloses a communication system for distribution of a bearer format type information among network elements located along a bearer path of a communication session. The bearer format type information informs of bearer format types supported by each of the network elements.

[0010] Document EP 1 465 445 A1 discloses a method involving comparing information in a transmission protocol regarding the codec mode to be used in the connections in a switching device (MSC) for at least two connection parts of an end-to-end connection to a media gateway. If the information is different then signaling to Trans Break Equipment (TBE) is carried out. Matching codec mode information for the connection parts is determined by the Trans Break Equipment.

[0011] Document TS 23 153: "Draft TS 23.153 Version 2.1.0", 3GPP Draft, vol. CN WG4, 2001 discloses general handling procedures for media gateway control procedures for codec handling.

[0012] Document US 2005/0076108 A1 discloses that packets associated with a call/session are received and processed at a media gateway. For the first few received media packets associated with a session, the media gateway uses various unique methods to learn the actual source IP address and UDP port assigned to the remote communication terminal by its customer-premises Network Address Translators (NATs) to the media flows of the current session. After the remote IP and UDP are learned, the media gateway reconfigures its firewall filtering function to check both the dynamically learned remote IP and UDP and the locally assigned IP and UDP of the current session.

[0013] Thus, in light of the difficulties associated with providing transcoder-free operation in media gateway, there exists a need for improve methods, systems, and computer program products for providing transcoder-free operation in a media gateway.

SUMMARY



[0014] According to one aspect, the subject matter described herein includes a method for implementing transcoder-free operation in a media gateway. The method includes receiving lists of media encoding rates and corresponding indices used by first and second endpoints of a media stream connection. Next, it is determined whether transcoder-free operation is possible for the media stream connection. In response to determining that transcoder-free operation is possible, a transcoder-free connection is established in the media gateway between the first and second media endpoints using a single digital signal processor in a first voice server to monitor and map between indices and encoding rates used by the first and second media endpoints during the media stream connection. Establishing a transcoder-free connection includes establishing a first connection between the first media endpoint and the first voice server, establishing a second connection between the second media endpoint and a second voice server, and replacing the second connection with a third connection between the second media endpoint and the first voice server.

[0015] The subject matter described herein may be implemented using a computer program product comprising computer executable instructions embodied in a computer readable medium. Exemplary computer readable media suitable for implementing the subject matter described herein include chip memory devices, disc memory devices, application specific integrated circuits, programmable logic devices, and downloadable electrical signals. In addition, a computer program product that implements a subject matter described herein may reside on a single device or computing platform or maybe distributed across multiple devices or computing platforms.

BRIEF DESCRIPTION OF THE DRAWINGS



[0016] Preferred embodiments of the subject matter described herein will now be explained with reference to the accompanying drawings of which:

Figure 1 is a block diagram illustrating transcoding in a telecommunications network;

Figure 2 is a block diagram illustrating a conventional transcoder-free operation implementation in a media gateway;

Figure 3 is a flow chart illustrating a method for implementing transcoder-free operation in a media gateway according to an embodiment of the subject matter described herein;

Figure 4 is a block diagram illustrating exemplary components for implementing transcoder-free operation in a media gateway according to an embodiment of the subject matter described herein;

Figure 5 is a block diagram illustrating an exemplary transcoder-free operation (TrFO) over Ethernet protocol stack that may be implemented in a media gateway according to an embodiment of the subject matter described herein;

Figure 6 is a block diagram of a media gateway including an Ethernet switching fabric for implementing transcoder-free operation according to an embodiment of the subject matter described herein;

Figure 7 is a block diagram illustrating an exemplary method for implementing transcoder-free operation in a media gateway according to an embodiment of the subject matter described herein; and

Figure 8 is a block diagram illustrating an alternate method for implementing transcoder-free operation in a media gateway according to an embodiment of the subject matter described herein.


DETAILED DESCRIPTION OF THE INVENTION



[0017] According to one aspect, the subject matter described herein includes a method for implementing transcoder-free operation in a media gateway. Figure 3 is a flow chart illustrating the exemplary steps for implementing transcoder-free operation in a media gateway according to an embodiment of the subject matter described herein. Referring to Figure 3, in step 300, lists of media encoding rates and corresponding indices used by endpoints of a media stream connection are received. These lists may be received by the control module of the media gateway. The control module may forward the lists to an internal processor associated with controlling voice processing functions of the media gateway. In step 302, the internal processor determines whether transcoder-free operation is possible. Determining whether transcoder-free operation is possible may include examining ingress and egress codec rates to determine whether the rates are compatible.

[0018] In step 304, if it is determined that transcoder-free operation is not possible, control proceeds to step 306 where a connection with transcoding is established between endpoints over an Ethernet switching fabric. In step 304, if it is determined that transcoder-free operation is possible, control proceeds to step 308 where a transcoder-free operation connection is established between endpoints over the Ethernet switching fabric in a media gateway using a single DSP to monitor and vary encoding rates.

[0019] Figure 4 is a block diagram illustrating exemplary components for providing transcoder-free operation in a media gateway according to an embodiment of the subject matter described herein. Referring to Figure 4, a codec/DSP 400 implements an IuUP/NbUP protocol stack 402 for both endpoints of a connection and performs radio access bearer sub-flow combination indicator (RFCI) mapping for a transcoder-free operation connection. A single DSP 400 is used to implement the transcoder-free operation. A second codec, such as that illustrated in Figure 2, is not utilized. As a result, the solution illustrated in Figure 4 reduces the resources required to implement transcoder-free operation in a media gateway. In addition, connections between the endpoints and codec 400 are established over an Ethernet switching fabric, schematically illustrated in Figure 4 by dual arrows 404.

[0020] Figure 5 is a block diagram illustrating protocol stack 402 in more detail. In Figure 5, protocol stack 402 includes a first IuUP/NbUP layer 500 and a first Ethernet interface layer 502 for interfacing with one endpoint of a TrFO connection. In addition, protocol stack 402 includes a second IuUP/NbUP layer 504 and second Ethernet interface layer 506 for interfacing with the other endpoint of a TrFO connection. An RFCI mapping layer 508 maps between codec rates used by the different endpoints of a TrFO connection. It should be noted that layers 500, 504, and 508 may be implemented by a DSP. It should be noted from Figure 5 that a single DSP 400 is used to implement the IuUP/NbUP layers for each endpoint of a connection as well as to perform the RFCI mapping. Ethernet interface layers 502 and 506 may be implemented a an Ethernet interface that connects the DSP to an Ethernet switching fabric. Using a single DSP to perform AMR rate monitoring and RFCI mapping reduces the resources required to implement TrFO in a media gateway over the implementation illustrated in Figure 2.

[0021] Figure 6 is a block diagram illustrating a media gateway for implementing transcoder-free operation according to an embodiment of the subject matter described herein. The architecture illustrated in Figure 6 corresponds to a media gateway having an Ethernet switching fabric, as described in commonly-assigned, co-pending U.S. patent application no. 11/138,990, filed May 26, 2005, the disclosure of which is incorporated herein by reference in its entirety. Referring to Figure 6, media gateway 600 includes a plurality of voice servers 602 for performing voice processing functions. In the illustrated example, each voice server 602 includes a voice over packet chip 604, a time slot interconnection 610, CPU 612, DSP 400, and an Ethernet interface 614. Voice over packet chip 604 encapsulates and removes voice information from IP packets and forwards the information to DSP 400 for further processing. Voice over packet chip 604 may also perform ATM adaptation layer one and layer two functions, respectively. DSP 400 performs transcoding, echo-cancellation, and other payload translation functions. According to an aspect of the subject matter described herein, each DSP 400 may implement the IuUP/NbUP protocol stack with RFCI mapping described above. TSI 610 makes on demand connections between voice over IP chip channels, TDM matrix channels and DSPs. CPU 612 controls the overall operation of each voice server module 602. Ethernet interfaces 614 connect each voice server module 602 with other modules that are connected to an Ethernet switching fabric 616.

[0022] Media gateway 600 also includes broadband network interfaces 617 that connect media gateway to external networks for receiving media packets from the networks. Broadband network interfaces 617 may include IP network interfaces as well as ATM network interfaces. Each broadband network interface 617 may include a network processor 618, a connection table 619, and an internal Ethernet interface 620. Network processors 618 control the overall operation of each broadband network interface 617. For example, network processors 618 may control the writing of data to each connection table 618. Each connection table 619 maintains connection data for forwarding media packets to the correct voice server. Internal Ethernet interfaces 620 connect each broadband network interface 617 to Ethernet switching fabric 616.

[0023] Ethernet switching fabric 616 interconnects voice server 602 and broadband interface 617. In the illustrated example, Ethernet switching fabric 616 includes a plurality of ports, numbered one through five. Five ports are shown for illustrative purposes only. It is understood that Ethernet switching fabric 616 may include fewer or more than five ports, depending on the number of devices connected to Ethernet switching fabric 616.

[0024] Media gateway 600 also includes a TDM matrix module 622 for switching TDM time slots between TDM network interfaces 624 and voice servers 602. TDM network interfaces 624 connect media gateway 600 to external TDM devices, such as TDM enabled end offices.

[0025] A control module 626 controls the overall operation of media gateway 600. In the illustrated example, control module 626 includes a TrFO controller 628 for receiving information from CPUs 612 of each voice server module regarding ingress and egress encoding rates and indices, determining whether TrFO is possible, and instructing voice server module 602 and network interfaces 617 to implement TrFO over Ethernet switching fabric 616. Control module 626 also communicates with an external media gateway controller 630. Media gateway controller 630 controls the establishment of connections by media gateway 600 using a media gateway control protocol, such as MEGACO or MGCP.

[0026] Figure 7 is a block diagram illustrating exemplary steps for achieving TrFO in media gateway 600 according to one embodiment of the subject matter described herein. Referring to Figure 7, a first media stream connection (labeled 1) is established between a first network endpoint, such as a node in RNC/core network 205 that interfaces directly or indirectly with a first mobile phone 700, and a first voice server 602A. A second media stream connection (labeled 2) is established between the second endpoint, such as a node in RNC/core network 205 that interfaces directly or indirectly with mobile phone 702, and a second voice server 602B. A third media connection (labeled 3) is established between broadband interface card 617 and voice server card 602B. Once the control module determines a transcoder-free operation is possible, the control module instructs broadband interface card 617 to replace connection 1 with connection 3. Replacing connection 1 with connection 3 may include instructing broadband interface card 617 to update its connection table 619 to reflect the new connection for the call. In addition, replacing connection 1 with connection 3 may include instructing voice server 602B to implement the NbUP/IuUP protocol stack and RFCI mapping function described above.

[0027] Tables 1 and 2 shown below illustrate the status of connection table 619 of broadband network interface card 617 before and after transcoder free operation is implemented. Tables 1 and 2 each include a first column indicating the external or network VPI/VCI value associated with incoming ATM cells that carry voice. The second column in each table includes a new VPI/VCI value used internally between the voice server cards and the network interfaces. The third column includes the voice server MAC address corresponding to the connection. It can be seen that in Table 1, before transcoder-free operation is established, the connection to each endpoint includes a separate voice server MAC address. In Table 2, after transcoder free operation is implemented, the voice server MAC address corresponding to both endpoints of the connection is Ethernet address ETH1, which corresponds to a single voice server card.
Table 1: Broadband Interface Connection Table Before TrFO
External VPI/VCI New VPI/VCI Voice Server MAC Addr.
100/1 110/1 Eth 0
100/2 110/2 Eth 1
Table 2: Broadband Interface Connection Table After TrFO
External VPI/VCI New VPI/VCI Voice Server MAC Addr.
100/1 110/3 Eth 1
100/2 110/2 Eth 1


[0028] An important function performed by a DSP once a TrFO connection is established is RFCI mapping. In order to perform such mapping, the DSP may maintain separate RFCI values for each connection endpoint. Tables 3 and 4 shown below are examples of RFI values that may be maintained by a DSP on a voice server card according to an embodiment of the subject matter described herein.
Table 3: RFCI Values and Rates for Endpoint A
Channel Index Rate
1 12.2k
2 10.2k
3 7.95k
4 6.7k
Table 3: RFCI Values and Rates for Endpoint B
Channel Index Rate
5 12.2k
6 10.2k
7 7.95k
8 6.7k


[0029] From Tables 1 and 2, the channel index and the corresponding rates for each endpoint can be determined. Once the DSP knows the indices and corresponding rates, the DSP can perform mappings between indices used by different endpoints. In the examples illustrated in Tables 3 and 4, the mappings would be 1-5, 2-6, 3-7, and 4-8.

[0030] Figure 8 is a block diagram illustrating an alternate method for implementing TrFO in a media gateway according to an embodiment of the subject matter described herein. Referring to Figure 8, a first media stream connection (labeled 1) is established between the endpoint that connects to mobile phone 700 and voice server 602A. A second media connection (labeled 2) is established between the endpoint that connects to mobile phone 702 and voice server 602B. Once TrFO controller 628 (illustrated in Figure 6) that determines transcoder-free operation is possible, TrFO controller 628 instructs voice server 602A to perform a loop back function and to initiate a connection (labeled 3) with voice server 602B. Implementing a loop back connection at voice server 602A means that the DSP on voice server 602A is not impacted. Thus, even though the solution illustrated in Figure 8 requires two voice servers, DSP processing resources are conserved over conventional TrFO implementations in media gateway, because DSP resources on the voice server where the loop back is implemented are not used.

[0031] Thus, the subject matter described herein includes methods, systems, and computer program products for implementing TrFO in media gateway. The subject matter includes utilizing a single DSP that implements an IbUP/NbUP protocol stack and RFCI mapping for both ends of a TrFO connection. In addition, the TrFO connection is established over an Ethernet switching fabric. Because only a single DSP is required, DSP processing resources are conserved over conventional TrFO implementations. Because an Ethernet switching fabric is used instead of an ATM switching fabric, the cost and complexity of the media gateway are reduced.

[0032] It will be understood that various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description is for the purpose of illustration only, and not for the purpose of limitation, as the invention is defined by the claims as set forth hereinafter.


Claims

1. A method for implementing transcoder-free operation in a media gateway, the method comprising:

a) receiving (300) first and second lists of media encoding rates and corresponding indices used by first and second media endpoints of a media stream connection;

b) determining (302) whether transcoder-free operation is possible for the media stream connection based on the first and second lists; and

c) in response to determining that transcoder-free operation is possible for the media stream connection, establishing (308) a transcoder-free connection over a packet switching fabric in the media gateway between the first and second media endpoints (700;702) using a single digital signal processor, DSP, in a first voice server (602A) to monitor and map between indices and encoding rates used by the first and second endpoints during the media stream connection,

characterized in that establishing a transcoder-free connection includes establishing a first connection between the first media endpoint (700) and the first voice server (602A), establishing a second connection between the second media endpoint (702) and a second voice server (602B), and replacing the second connection with a third connection between the second media endpoint (702) and the first voice server (602A), wherein replacing the second connection with the third connection includes instructing a broadband interface card in the media gateway to update a connection table to reflect the third connection and instructing the second voice server (602B) to implement a dual NbUP/IuUP protocol stack (402) that includes a first NbUP/IuUP layer (500), a second NbUP/IuUP layer (504), and a radio access bearer sub-flow combination indicator RFCI mapping layer (508) that maps the encoding rates used by the first and second endpoints.
 
2. The method of claim 1, wherein receiving (300) first and second lists of media encoding rates and corresponding indices includes receiving first and second fists of radio access bearer sub-flow combination indicators, RFCIs, and corresponding media encoding rates used by the first and second endpoints.
 
3. The method of claim 1, wherein determining (302) whether transcoder-free operation is possible includes determining whether the media encoding rates in the first list are compatible with those in the second list.
 
4. The method of claim 1, wherein the packet switching fabric includes an Ethernet switching fabric.
 
5. The method of claim 1, comprising, after establishing the transcoder-free connection, performing radio access bearer sub-flow combination indicator, RFCI, mapping for the connection.
 
6. A media gateway (600), comprising:

a broadband interface (617) for sending media packets to and receiving media packets from an external network;

a packet switching fabric (616) for forwarding media packets between the broadband interface and at least one internal processing resource in the media gateway;

at least one voice server (602) for performing voice processing functions, including transcoding, for the media packets, wherein the at least one voice server includes a first voice server (602A) and a second voice server (602B), wherein each of the first voice server (602A) and the second voice server (602B) includes a single digital signal processor, DSP, (400) for monitoring and mapping between indices and encoding rates used by a first media endpoint (700) and a second media endpoint (702) of a transcoder-free connection; and

a transcoder-free operation controller (628) for establishing the transcoder-free connection between the broadband interface (617) and the first voice server (602A) via the switching fabric (616),

characterized in that the transcoder-free operation controller (628) establishes the transcoder-free connection by establishing a first connection between the first media endpoint (700) and the first voice server (602A), establishing a second connection between the second media endpoint (700) and the second voice server (602B), and replacing the second connection with a third connection between the second media endpoint (702) and the first voice server (602A), wherein replacing the second connection with the third connection includes instructing a broadband interface card in the media gateway to update a connection table to reflect the third connection and instructing the second voice server (602B) to implement a dual NbUP/IuUP protocol stack (402) that includes a first NbUP/IuUP layer (500), a second NbUP/IuUP layer (504), and a radio access bearer sub-flow combination indicator RFCI mapping layer (508) that maps the encoding rates used by the first and second endpoints.


 
7. The media gateway (600) of claim 6, wherein the broadband interface (617) comprises an IP interface.
 
8. The media gateway (600) of claim 6, wherein the broadband interface (617) comprises an ATM interface.
 
9. The media gateway (600) of claim 6, wherein the packet switching fabric (616) comprises an Ethernet switching fabric.
 
10. The media gateway (600) of claim 6, wherein the packet switching fabric comprises an ATM switching fabric.
 
11. The media gateway (600) of claim 6, wherein the transcoder-free operation controller (628) is adapted to determine whether transcoder-free operation is possible by examining the encoding rates used by the first media endpoint and the second media endpoint.
 
12. The media gateway (600) of claim 6, wherein the first voice server (602B) is adapted to perform radio access bearer sub-flow combination indicator, RFCI, mapping for the transcoder-free connection.
 
13. A computer program product comprising computer executable instructions embodied in a computer readable medium for performing steps comprising:

a) receiving (300) first and second lists of media encoding rates and corresponding indices used by first and second media endpoints (700; 702) of a media stream connection;

b) determining (302) whether transcoder-free operation is possible for the media stream connection based on the first and second lists; and

c) in response to determining that transcoder-free operation is possible for the media stream connection, establishing (308) a transcoder-free connection over a packet switching fabric in a media gateway between the first and second media endpoints (700; 702) using a single digital signal processor, DSP, (400) in a first voice server (602A) to monitor and map between indices and encoding rates used by the first and second endpoints during the media stream connection,

characterized in that establishing a transcoder-free connection includes establishing a first connection between the first media endpoint (700) and the first voice server (602A), establishing a second connection between the second media endpoint (702) and a second voice server (602B), and replacing the second connection with a third connection between the second media endpoint (702) and the first voice server (602A), wherein replacing the second connection with the third connection includes instructing a broadband interface card in the media gateway to update a connection table to reflect the third connection and instructing the second voice server (602B) to implement a dual NbUP/IuUP protocol stack (402) that includes a first NbUP/IuUP layer (500), a second NbUP/IuUP layer (504), and a radio access bearer sub-flow combination indicator RFCI mapping layer (508) that maps the encoding rates used by the first and second endpoints.
 


Ansprüche

1. Verfahren zum Implementieren des Transcoder-freien Betriebs eines Media Gateways, das Folgendes umfasst:

(a) Empfangen (300) einer ersten und einer zweiten Liste von Medien-Kodierraten und zugehörigen Indizes, die von einem ersten und einem zweiten Medien-Endpunkt einer Medien-Datenstromverbindung verwendet werden;

(b) Ermitteln (302), ob Transcoder-freier Betrieb für die Medien-Datenstromverbindung auf Grundlage der ersten und der zweiten Liste möglich ist; und

(c) Einrichten (308), in Antwort auf das Ermitteln, dass der Transcoder-freie Betrieb für die Medien-Datenstromverbindung möglich ist, einer Transcoder-freien Verbindung über eine Paketvermittlungsleitung in dem Media Gateway zwischen dem ersten und dem zweiten Medien-Endpunkt (700; 702) durch einen einzelnen digitalen Signalprozessor, DSP, in einem ersten Voiceserver (602A), um Indizes und Kodierraten zu überwachen und auf einander abzubilden, die von dem ersten und dem zweiten Endpunkt während der Medien-Datenstromverbindung verwendet werden,

dadurch gekennzeichnet, dass das Einrichten einer Transcoder-freien Verbindung Folgendes umfasst:

Einrichten einer ersten Verbindung zwischen dem ersten Medien-Endpunkt (700) und dem ersten Voiceserver (602A), Einrichten einer zweiten Verbindung zwischen dem zweiten Medien-Endpunkt (702) und einem zweiten Voiceserver (602B) und Ersetzen der zweiten Verbindung mit einer dritten Verbindung zwischen dem zweiten Medien-Endpunkt (702) und dem ersten Voiceserver (602A), wobei das Ersetzen der zweiten Verbindung mit der dritten Verbindung das Anweisen einer Breitband-Schnittstellenkarte in dem Media Gateway, eine Verbindungstabelle zu aktualisieren, um die dritte Verbindung wiederzugeben, und das Anweisen des zweiten Voiceservers (602B), einen dualen NbUP/IuUP-Protokollstapel (402) zu implementieren, der eine erste NbUP/IuUP-Schicht (500), eine zweite NbUP/IuUP-Schicht (504) und eine Mapping-Schicht (508) für Radio Access Bearer Sub-Flow-Combination-Indikatoren, RFCI, umfasst, welche die Kodierraten abbildet, die von dem ersten und dem zweiten Endpunkt verwendet werden.


 
2. Verfahren nach Anspruch 1, wobei das Empfangen (300) der ersten und der zweiten Liste von Media-Kodierraten und zugehörigen Indizes das Empfangen einer ersten und einer zweiten Liste von Radio Access Bearer Sub-Flow-Combination-Indikatoren, RFCI, und zugehöriger Medien-Kodierraten umfasst, die von dem ersten und dem zweiten Endpunkt verwendet werden.
 
3. Verfahren nach Anspruch 1, wobei das Ermitteln (302), ob ein Transcoder-freier Betrieb möglich ist, das Ermitteln umfasst, ob die Media-Kodierraten in der ersten Liste mit denen in der zweiten Liste vereinbar sind.
 
4. Verfahren nach Anspruch 1, wobei die Paketvermittlungsleitung eine Ethernet-Vermittlungsleitung umfasst.
 
5. Verfahren nach Anspruch 1, das nach dem Einrichten der Transcoder-freien Verbindung das Ausführen von Mapping mit Radio Access Bearer Sub-Flow-Combination-Indikatoren, RFCI, für die Verbindung umfasst.
 
6. Media Gateway (600), das Folgendes umfasst:

eine Breitbandschnittstelle (617) zum Versenden von Medien-Paketen an und Empfangen von Medien-Paketen von einem externen Netzwerk;

eine Paketvermittlungsleitung (616) zum Weiterleiten von Medien-Paketen zwischen der Breitbandschnittstelle und mindestens einer internen Verarbeitungsressource in dem Media Gateway;

Mindestens einen Voiceserver (602) zum Ausführen von Sprach-Verarbeitungsfunktionen einschließlich Transkodierung, für die Medien-Pakete, wobei der mindestens eine Voiceserver einen ersten Voiceserver (602A) und einen zweiten Voiceserver (602B) umfasst, wobei sowohl der erste Voiceserver (602A) als auch der zweite Voiceserver (602B) einen einzigen digitalen Signalprozessor, DSP, (400) zum Überwachen und Abbilden zwischen Indizes und Kodierraten umfasst, die von einem ersten Medien-Endpunkt (700) und einem zweiten Medien-Endpunkt (702) einer Transcoder-freien Verbindung verwendet werden; und

eine Transcoder-freie Betriebssteuerung (628) zum Einrichten der Transcoder-freien Verbindung zwischen der Breitbandschnittstelle (617) und dem ersten Voiceserver (602A) über die Vermittlungsleitung (616),

dadurch gekennzeichnet, dass

die Transcoder-freie Betriebssteuerung (628) die Transcoder-freie Verbindung einrichtet, indem eine erste Verbindung zwischen dem ersten Medien-Endpunkt (700) und dem ersten Voiceserver (602) eingerichtet wird, eine zweite Verbindung zwischen dem zweiten Medien-Endpunkt (702) und dem zweiten Voiceserver (602B) eingerichtet wird und die zweite Verbindung mit einer dritten Verbindung zwischen dem zweiten Medien-Endpunkt (702) und dem ersten Voiceserver (602A) ersetzt wird, wobei das Ersetzen der zweiten Verbindung mit der dritten Verbindung das Anweisen einer Breitbandschnittstellenkarte in dem Media Gateway, so dass eine Verbindungstabelle aktualisiert wird, um die dritte Verbindung widerzuspiegeln, und das Anweisen des zweiten Voiceservers (602B) umfasst, einen dualen NbUP/IuUP-Protokollstapel (402) zu implementieren, der eine erste NbUP/IuUP-Schicht (500), eine zweite NbUP/IuUP-Schicht (504) und eine Mapping-Schicht für Radio Access Bearer Sub-Flow-Combination-Indikatoren, RFCI, umfasst, die die Kodierraten abbildet, die von dem ersten und dem zweiten Endpunkt verwendet werden.


 
7. Media Gateway (600) nach Anspruch 6, wobei die Breitbandschnittstelle (617) eine IP-Schnittstelle umfasst.
 
8. Media Gateway (600) nach Anspruch 6, wobei die Breitbandschnittstelle (617) eine ATM-Schnittstelle umfasst.
 
9. Media Gateway (600) nach Anspruch 6, wobei die Paketvermittlungsleitung (616) eine Ethernet-Vermittlungsleitung umfasst.
 
10. Media Gateway (600) nach Anspruch 6, wobei die Paketvermittlungsleitung eine ATM-Vermittlungsleitung umfasst.
 
11. Media Gateway (600) nach Anspruch 6, wobei die Transcoder-freie Betriebssteuerung (628) geeignet ist, zu ermitteln, ob der Transcoder-freie Betrieb möglich ist, indem die Kodierraten untersucht werden, die von dem ersten Medien-Endpunkt und dem zweiten Medien-Endpunkt verwendet werden.
 
12. Media Gateway (600) nach Anspruch 6, wobei der erste Voiceserver (602B) geeignet ist, Mapping durch Radio Access Bearer Sub-Flow-Combination-Indikatoren, RFCI, für die Transcoder-freie Verbindung auszuführen.
 
13. Computerprogramm-Produkt, das durch Computer ausführbare Befehle umfasst, die in einem Computer-lesbaren Medium ausgeführt sind, um Schritte auszuführen, die Folgendes umfassen:

(a) Empfangen (300) einer ersten und einer zweiten Liste von Medien-Kodierraten und zugehörigen Indizes, die von einem ersten und einem zweiten Medien-Endpunkt (700; 702) einer Medien-Datenstromverbindung verwendet werden;

(b) Ermitteln (302), ob Transcoder-freier Betrieb für die Medien-Datenstromverbindung auf Grundlage der ersten und der zweiten Liste möglich ist; und

(c) Einrichten (308), in Antwort auf das Ermitteln, dass der Transcoder-freie Betrieb für die Medien-Datenstromverbindung möglich ist, einer Transcoder-freien Verbindung über eine Paketvermittlungsleitung in einem Media Gateway zwischen dem ersten und dem zweiten Medien-Endpunkt (700; 702) durch einen einzelnen digitalen Signalprozessor, DSP, (400) in einem ersten Voiceserver (602A), um Indizes und Kodierraten zu überwachen und auf einander abzubilden, die von dem ersten und dem zweiten Endpunkt während der Medien-Datenstromverbindung verwendet werden,

dadurch gekennzeichnet, dass das Einrichten einer Transcoder-freien Verbindung Folgendes umfasst:

Einrichten einer ersten Verbindung zwischen dem ersten Medien-Endpunkt (700) und dem ersten Voiceserver (602A), Einrichten einer zweiten Verbindung zwischen dem zweiten Medien-Endpunkt (702) und einem zweiten Voiceserver (602B) und Ersetzen der zweiten Verbindung mit einer dritten Verbindung zwischen dem zweiten Medien-Endpunkt (702) und dem ersten Voiceserver (602A), wobei das Ersetzen der zweiten Verbindung mit der dritten Verbindung das Anweisen einer Breitband-Schnittstellenkarte in dem Media Gateway, eine Verbindungstabelle zu aktualisieren, um die dritte Verbindung wiederzugeben, und das Anweisen des zweiten Voiceservers (602B), einen dualen NbUP/IuUP-Protokollstapel (402) zu implementieren, umfasst, der eine erste NbUP/IuUP-Schicht (500), eine zweite NbUP/IuUP-Schicht (504) und eine Mapping-Schicht (508) für Radio Access Bearer Sub-Flow-Combination-Indikatoren, RFCI, umfasst, welche die Kodierraten abbildet, die von dem ersten und dem zweiten Endpunkt verwendet werden.


 


Revendications

1. Procédé pour mettre en oeuvre un fonctionnement sans transcodeur dans une passerelle média, le procédé comprenant :

a) recevoir (300) de première et seconde listes de taux d'encodage de médias et d'indices correspondants utilisés par de premier et second points d'extrémité médias d'une connexion de flux médias ;

b) déterminer (302) si un fonctionnement sans transcodeur est possible pour la connexion de flux médias sur la base des première et seconde listes ; et

c) en réponse à la détermination qu'un fonctionnement sans transcodeur est possible pour la connexion de flux médias, établir (308) une connexion sans transcodeur sur une matrice de commutation de paquets dans la passerelle média entre les premier et second points d'extrémité médias (700 ; 702) en utilisant un processeur de signaux numériques, DSP, unique dans un premier serveur vocal (602A) pour surveiller et effectuer un mappage entre des indices et des taux de codage utilisés par les premier et second points d'extrémité lors de la connexion de flux médias,

caractérisé en ce que l'établissement d'une connexion sans transcodeur comprend :

établir une première connexion entre le premier point d'extrémité média (700) et le premier serveur vocal (602A), établir une seconde connexion entre le second point d'extrémité média (702) et un second serveur vocal (602B), et remplacer la seconde connexion par une troisième connexion entre le second point d'extrémité média (702) et le premier serveur vocal (602A), dans lequel le remplacement de la seconde connexion par la troisième connexion comprend de donner l'ordre à une carte d'interface à large bande dans la passerelle média de mettre à jour une table de connexion pour refléter la troisième connexion, et de donner l'ordre au second serveur vocal (602B) de mettre en oeuvre une pile de protocoles doubles NbUP/luUP (402) qui comprend une première couche NbUP/luUP (500), une seconde couche NbUP/luUP (504), et une couche de mappage d'indicateurs de combinaison de sous-flux de support d'accès radio, RFCI, (508) qui mappe les taux de codage utilisés par les premier et second points d'extrémité.


 
2. Procédé selon la revendication 1, dans lequel la réception (300) de première et seconde listes de taux de codage de médias et d'indices correspondants comprend de recevoir de première et seconde listes d'indicateurs de combinaison de sous-flux de support d'accès radio, RFCI, et de taux de codage de médias correspondants utilisées par les premier et second points d'extrémité.
 
3. Procédé selon la revendication 1, dans lequel la détermination (302) pour savoir si un fonctionnement sans transcodeur est possible comprend de déterminer si les taux de codage de médias dans la première liste sont compatibles avec ceux de la seconde liste.
 
4. Procédé selon la revendication 1, dans lequel la matrice de commutation de paquets comprend une matrice de commutation Ethernet.
 
5. Procédé selon la revendication 1, comprenant, après avoir établi la connexion sans transcodeur, d'effectuer un mappage d'indicateurs de combinaison de sous-flux de support d'accès radio, RFCI, pour la connexion.
 
6. Passerelle de média (600), comprenant :

une interface à large bande (617) pour envoyer des paquets médias à un réseau externe et recevoir des paquets médias à partir d'un réseau externe ;

une matrice de commutation de paquets (616) pour transmettre des paquets médias entre l'interface à large bande et au moins une ressource de traitement interne de la passerelle média ;

au moins un serveur vocal (602) pour exécuter des fonctions de traitement vocal, y compris un transcodage, pour les paquets médias, dans lequel ledit au moins un serveur vocal comprend un premier serveur vocal (602A) et un second serveur vocal (602B), dans lequel chacun du premier serveur vocal (602A) et du second serveur vocal (602B) comprend un processeur de signaux numériques, DSP, unique (400) pour surveiller et effectuer un mappage entre des indices et des taux de codage utilisés par un premier point d'extrémité média (700) et un second point d'extrémité média (702) d'une connexion sans transcodeur ; et

un contrôleur de fonctionnement sans transcodeur (628) pour établir la connexion sans transcodeur entre l'interface à large bande (617) et le premier serveur vocal (602A) par l'intermédiaire de la matrice de commutation (616),

caractérisée en ce que le contrôleur de fonctionnement sans transcodeur (628) établit la connexion sans transcodeur en établissant une première connexion entre le premier point d'extrémité média (700) et le premier serveur vocal (602A), en établissant une seconde connexion entre le second point d'extrémité média (702) et le second serveur vocal (602B), et en remplaçant la seconde connexion par une troisième connexion entre le second point d'extrémité média (702) et le premier serveur vocal (602A), dans laquelle le remplacement de la seconde connexion par la troisième connexion comprend de donner l'ordre à une carte d'interface à large bande dans la passerelle média de mettre à jour une table de connexion pour refléter la troisième connexion, et de donner l'ordre au second serveur vocal (602B) de mettre en oeuvre une pile de protocoles doubles NbUP/IuUP (402) qui comprend une première couche NbUP/IuUP (500), une seconde couche NbUP/IuUP (504), et une couche de mappage d'indicateurs de combinaison de sous-flux de support d'accès radio, RFCI, (508) qui mappe les taux de codage utilisés par les premier et second points d'extrémité.


 
7. Passerelle média (600) selon la revendication 6, dans laquelle l'interface à large bande (617) comprend une interface IP.
 
8. asserelle média (600) selon la revendication 6, dans laquelle l'interface à large bande (617) comprend une interface ATM.
 
9. Passerelle média (600) selon la revendication 6, dans laquelle la matrice de commutation de paquets (6116) comprend une matrice de commutation Ethernet.
 
10. Passerelle média (600) selon la revendication 6, dans laquelle la matrice de commutation de paquets comprend une matrice de commutation ATM.
 
11. Passerelle média (600) selon la revendication 6, dans laquelle le contrôleur de fonctionnement sans transcodeur (628) est conçu pour déterminer si un fonctionnement sans transcodeur est possible en examinant les taux de codage utilisés par le premier point d'extrémité média et le second point d'extrémité média.
 
12. Passerelle média (600) selon la revendication 6, dans laquelle le premier serveur vocal (602A) est conçu pour effectuer un mappage d'indicateurs de combinaison de sous-flux de support d'accès radio, RFCI, pour la connexion sans transcodeur.
 
13. Produit de programme informatique comprenant des instructions exécutables par ordinateur incorporées dans un support lisible par ordinateur pour effectuer les étapes consistant à :

a) recevoir (300) de première et seconde listes de taux d'encodage de médias et d'indices correspondants utilisés par de premier et second points d'extrémité médias (700 ; 702) d'une connexion de flux médias ;

b) déterminer si un fonctionnement sans transcodeur est possible pour la connexion de flux médias sur la base des première et seconde listes ; et

c) en réponse à la détermination qu'un fonctionnement sans transcodeur est possible pour la connexion de flux médias, établir (308) une connexion sans transcodeur sur une matrice de commutation de paquets dans la passerelle média entre les premier et second points d'extrémité médias (700 ; 702) en utilisant un processeur de signaux numériques, DSP, unique dans un premier serveur vocal (602A) pour surveiller et effectuer un mappage entre des indices et des taux de codage utilisés par les premier et second points d'extrémité lors de la connexion de flux médias,

caractérisé en ce que l'établissement d'une connexion sans transcodeur comprend :

établir une première connexion entre le premier point d'extrémité média (700) et le premier serveur vocal (602A), établir une seconde connexion entre le second point d'extrémité média (702) et un second serveur vocal (602B), et remplacer la seconde connexion par une troisième connexion entre le second point d'extrémité média (702) et le premier serveur vocal (602A), dans lequel le remplacement de la seconde connexion par la troisième connexion comprend de donner l'ordre à une carte d'interface à large bande dans la passerelle média de mettre à jour une table de connexion pour refléter la troisième connexion et de donner l'ordre au second serveur vocal (602B) de mettre en oeuvre une pile de protocoles doubles NbUP/luUP (402) qui comprend une première couche NbUP/luUP (500), une seconde couche NbUP/luUP (594), et une couche de mappage d'indicateurs de combinaison de sous-flux de support d'accès radio, RFCI, (508) qui mappe les taux de codage utilisés par les premier et second points d'extrémité.


 




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Cited references

REFERENCES CITED IN THE DESCRIPTION



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Patent documents cited in the description